Evidence for a significant role of gastrin in cysteamine-induced hypersecretion of gastric acid.
Cysteamine has been known to stimulate gastric acid secretion and to induce duodenal ulcers in rats. We investigated the role of gastrin in cysteamine-induced acid hypersecretion in the perfused rat stomach. Intravenous infusion of cysteamine (75 mg/kg/h) resulted in a significant increase in acid secretion, which was accompanied by a marked increase in the plasma gastrin concentration. The cysteamine-induced increase in gastric acid secretion was completely blocked by i.v. injection of anti-gastrin rabbit serum (500 microliters). In addition, i.v. infusion of a CCK-B/gastrin receptor antagonist (L-365,260) (1 mg/kg/h) also suppressed the cysteamine-induced increase in acid secretion. Atropine significantly, but only partially, inhibited the increase. The elevated plasma gastrin levels induced by cysteamine were unaffected by atropine and L-365,260. In conclusion, cysteamine-induced acid hypersecretion is mediated mainly by cysteamine-induced gastrin release and partially by cholinergic factors. Furthermore, gastrin release caused by cysteamine appears to be independent of cholinergic tone.
Shiratori
K
K
Department of Medicine, Tokyo Women's Medical College, Japan.
Shimizu
K
K
Ikeda
M
M
Watanabe
S
S
Hayashi
N
N
D000818:Animals; D001285:Atropine / Q000494:pharmacology; D001570:Benzodiazepinones / Q000494:pharmacology; D003543:Cysteamine; D005744:Gastric Acid / Q000378:metabolism*; D005753:Gastric Mucosa / Q000187:drug effects / Q000378:metabolism*; D005755:Gastrins / Q000276:immunology / Q000502:physiology*; D007106:Immune Sera / Q000494:pharmacology; D008297:Male; D010671:Phenylurea Compounds; D011817:Rabbits; D051381:Rats; D017208:Rats, Wistar; D043887:Receptor, Cholecystokinin B; D011949:Receptors, Cholecystokinin / Q000037:antagonists & inhibitors
D001570:Benzodiazepinones; D005755:Gastrins; D007106:Immune Sera; D010671:Phenylurea Compounds; D043887:Receptor, Cholecystokinin B; D011949:Receptors, Cholecystokinin; C058121:L 365260; D003543:Cysteamine; D001285:Atropine